JPH0696991A - Production of multilayer ceramic capacitor - Google Patents

Abstract

PURPOSE:To enhance yield and reliability while facilitating press bonding and delamination by forming a flattening pattern at least between the corner part and the opposing surface of a dielectric green sheet when a composite sheets are laminated and press bonded. CONSTITUTION:A dielectric green sheet 2 is formed on a supporting film 1 and an internal electrode pattern 3 is formed thereon thus preparing a plurality of composite sheets 5. In the composite sheet 5, a flattening pattern 4 is formed at least the corner part, e.g. the outer peripheral part, of the dielectric green sheet 2. The composite sheet 5 is then laminated on a first cover sheet 6 such that the inner electrode pattern 3 and the flattening pattern 4 are positioned on the first cover sheet 6 side and then they are press bonded. Subsequently, the supporting film 1 is delaminated thus forming a laminate. This method facilitates delamination of supporting film after press bonding of composite sheet.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a monolithic ceramic capacitor.

[0002]

2. Description of the Related Art Multilayer ceramic capacitors (hereinafter referred to as MLC
16), as shown in FIG. 16, a plurality of dielectric layers 31 made of ceramics, and internal electrodes 32 arranged between the dielectric layers 31 and having one end alternately exposed on opposite side surfaces.
And a pair of external electrodes 33 respectively provided on the opposite side surfaces. The MLC in FIG. 16 is a chip type, but in addition, a dip type in which a lead wire is attached and coated with resin is also known.

In recent years, such MLCs have been made smaller and have a larger capacity, and along with this, the thickness of the dielectric, which was previously about 20 μm per layer after sintering, is reduced to less than that. Is required.

By the way, the MLC has been conventionally manufactured by the following method. First, as shown in FIG. 17, a dielectric green sheet 41 made of a dielectric powder and an organic binder is formed, and an internal electrode pattern 42 is applied on the dielectric green sheet to produce a composite sheet 43. Subsequently, as shown in FIG. 18, the composite sheet 43 is formed.
Are stacked between the two cover sheets 44 and 45, heated and pressed to be integrated, and then cut in the thickness direction as shown by the alternate long and short dash line to cut out individual units. afterwards,
ML by sintering and baking a pair of external electrodes
Produce C.

However, in the conventional method, when a plurality of the composite sheets 43 are laminated, the dielectric green sheet 41 is mechanically too soft, and particularly, the thickness after sintering is 20 μm or less. Then, the dielectric green sheet 41 stretches, which makes it difficult to align the composite sheets 43 with high accuracy.

As a method of solving such a problem, there is known a method of using a composite sheet containing a support film for increasing mechanical strength.

For example, in Japanese Patent Laid-Open No. 62-63413, a dielectric green sheet is formed on a supporting film, an internal electrode pattern is formed on this dielectric green sheet, and the dielectric film is held on the supporting film. A method of manufacturing an MLC by repeating a pressure-bonding / peeling procedure in which an internal electrode pattern and the dielectric green sheet are placed on a mating member such as a cover sheet and pressure-bonded, and then only the support film is peeled is disclosed. .

In Japanese Patent Laid-Open No. 3-250612, two composite sheets each having a dielectric green sheet and an internal electrode pattern formed on a support film are used, and the dielectric green sheet and the dielectric green sheet on the composite sheet are used. A method for manufacturing an MLC by repeating the procedure of alternately press-bonding and peeling the internal electrode pattern to a mating member such as a cover sheet is disclosed.

Further, in Japanese Unexamined Patent Publication No. 63-188927, an internal electrode pattern is formed on a counter member such as a cover sheet, and a dielectric green sheet is formed on the internal electrode pattern to form a dielectric film. A method for manufacturing an MLC by repeating the procedure of pressing and peeling a green sheet is disclosed.

However, in any of the above-mentioned methods, a step (difference in thickness) always occurs between the location where the internal electrode pattern is not formed and the location other than that, so that the step causes the step in the crimping step. As a result, the adhesion between the dielectric green sheet and the mating member becomes smaller. as a result,
In the peeling step of the supporting film, there has been a problem that a part of the dielectric green sheet that should be originally transferred to the mating member together with the supporting film is peeled from the mating member while being adhered.

In order to eliminate the above-mentioned step, it can be considered to reduce the thickness of the internal electrode pattern itself. However, in addition to the difficulty of manufacturing the internal electrode pattern, if the thickness of the internal electrode pattern is too thin, the MLC acquisition capacity decreases and the internal electrode electrical resistance increases. It is difficult to reduce the thickness of the working pattern to, for example, about 3 μm or less. As a result, it is inevitable that a certain level difference will occur. . Further, since such a step is added up every time the number of laminated layers increases, the step increases as the number of layers increases, and the above-mentioned pressure bonding / peeling becomes difficult.

Meanwhile, in US Pat. No. 5,101,319, after forming an internal electrode pattern on a supporting film, a dielectric green sheet is filled on the internal electrode pattern so as to fill a step due to the internal electrode pattern. It is disclosed that an MLC is manufactured by forming the composite sheet while forming the composite sheet and repeating the above-mentioned pressure bonding and peeling using the composite sheet. However, in the above manufacturing method, since the internal electrode pattern is first formed on the support film, the thin dielectric green sheet formed thereafter has a non-uniform thickness after the drying process. Therefore, it becomes difficult to uniformly press and peel the support film.
In particular, as the number of layers increases, the unevenness of the surface of the dielectric green sheet increases, which makes it difficult to perform pressure bonding and peeling. Further, since the internal electrode pattern is present, cracks are likely to occur in the dielectric green sheet, especially during drying, which causes an electrical short circuit.

[0013]

SUMMARY OF THE INVENTION An object of the present invention is to enable good pressure bonding and peeling even if a thin dielectric green sheet having a thickness after sintering of 20 μm or less is formed.
It is intended to provide a method for manufacturing an LC.

[0014]

In the method for manufacturing an MLC according to the present invention, a dielectric green sheet is formed on a supporting film, and a plurality of internal electrode patterns made of a conductive paste are formed on the dielectric green sheet. And the first step of producing a plurality of composite sheets, and the composite sheet is superposed on the first cover sheet so that the internal electrode pattern is located on the first cover sheet side and pressure-bonded to the support film. A second step of peeling the laminated film to form a laminated film; a third step of sequentially laminating the remaining composite sheets on the laminated film in the same procedure as the second step to form a multilayer laminated film; And a fourth step of stacking a second cover sheet on the multilayer film, the method of manufacturing a multilayer ceramic capacitor comprising: Step difference cancellation pattern for eliminating a level difference of the internal electrode pattern between the Kutomo corner and the opposing surface of the corner portion is characterized in that the interposition.

In order to interpose the level difference eliminating pattern between at least the corner portion of the dielectric green sheet and the first cover sheet, the level difference is previously formed at least at the corner portion of the dielectric green sheet of the composite sheet. It is possible to employ a method of forming the elimination pattern, or a method of previously forming the step elimination pattern at a position corresponding to at least a corner portion of the dielectric green sheet of the mating member. In the manufacturing method of the MLC, the first cover sheet is used as the mating member for the first pressure-bonding / peeling of the composite sheet, and the second and subsequent times of the pressure-bonding / peeling of the composite sheet are the laminates formed in the previous step. The film becomes the mating member.

Hereinafter, in the method of manufacturing an MLC according to the present invention, (1) a case where the step eliminating pattern is formed at least at a corner portion of the dielectric green sheet of the composite sheet will be described with reference to FIGS. (2) A case in which the step difference eliminating pattern is previously formed at a position corresponding to at least a corner portion of the dielectric green sheet in the mating member will be described in detail with reference to FIGS. 5 to 7.

(1) First, as shown in FIGS. 1 and 2, a dielectric green sheet 2 is formed on a support film 1,
Internal electrode pattern 3 on the dielectric green sheet 2
To form a plurality of composite sheets 5. Further, in these composite sheets 5, the step eliminating pattern 4 is formed at least at a corner portion of the dielectric green sheet 2, for example, at an outer peripheral portion of the dielectric green sheet 2.
Subsequently, as shown in FIG. 3, the composite sheet 5 is overlapped and pressure-bonded onto the first cover sheet 6 so that the internal electrode pattern 3 and the step eliminating pattern 4 are located on the first cover sheet 6 side. . Subsequently, as shown in FIG. 4, the supporting film 1 is peeled off to form a laminated film.

Next, the remaining composite sheets are sequentially laminated by the same procedure as described above to form a multilayer laminated film, and then the second cover sheet is laminated. Subsequently, the obtained laminated body is heated and pressed, and cut in the thickness direction to cut out individual units. After that, the MLC is manufactured by sintering and baking a pair of external electrodes.

(2) First, as shown in FIG. 5, a dielectric green sheet 12 is formed on the first support film 11, and the internal electrode pattern 1 is formed on the dielectric green sheet 12.
3 is formed to produce a plurality of first composite sheets 14.

Further, as shown in FIG. 6, a step eliminating pattern 16 is formed on the second supporting film 15 at least at a corner portion of the dielectric green sheet, for example, at a position corresponding to an outer peripheral portion of the dielectric green sheet. A plurality of second composite sheets 17 are produced.

Then, the second composite sheet 17 is superposed on the first cover sheet 18 so that the step difference eliminating pattern 16 is located on the side of the first cover sheet 18, and then pressure-bonded, and then the second support film 15 is formed. Is peeled off and the step difference eliminating pattern 16 is transferred onto the first cover sheet 18. Then, the first composite sheet 14 is provided on the surface of the first cover sheet 18 on which the step eliminating pattern 16 is formed, and the internal electrode pattern 13 is provided on the first cover sheet 1.
After stacking and pressing so as to be positioned on the 8 side, the first supporting film 11 is peeled off to form a laminated film as shown in FIG. 7.

Then, by using the remaining first and second composite sheets in the same procedure as described above, the step difference eliminating pattern, the internal electrode pattern and the dielectric green sheet are sequentially laminated to form a multilayer laminated film. After forming, the second cover sheet is overlaid. Subsequently, the obtained laminated body is heated and pressed, and cut in the thickness direction to cut out individual units. After that, the MLC is manufactured by sintering and baking a pair of external electrodes.

Another MLC manufacturing method according to the present invention is as follows.
A first step of forming a plurality of first composite sheets by forming a dielectric green sheet on a first support film; and a plurality of internal electrode patterns made of a conductive paste on a second support film to form a plurality of internal electrode patterns. Second to make the second composite sheet
Step, and after stacking the second composite sheet on the first cover sheet from the internal electrode pattern side and press-bonding the second support film, peeling the first composite sheet from the dielectric green sheet side. Third step of forming a laminated film in which the internal electrode pattern and the dielectric green sheet are laminated by stacking and pressure bonding and peeling off the first support film, and the remaining first composite sheet, second
A fourth step of forming a multilayer laminated film by sequentially laminating a composite sheet on the laminated film in the same procedure as the third step, and a fifth step of laminating a second cover sheet on the multilayer laminated film. In the manufacturing method of the ceramic capacitor provided,
When the first composite sheet is stacked and pressure-bonded, a step-eliminating pattern for eliminating a step of the internal electrode pattern is formed between at least the corner portion of the dielectric green sheet and the facing surface of the corner portion. It is characterized by being interposed.

Hereinafter, in another MLC manufacturing method according to the present invention, (3) a case where a step eliminating pattern is formed in advance in at least a corner portion of the dielectric green sheet in the first composite sheet will be described with reference to FIGS. See
(4) FIG. 11 to FIG. 11 show a case where a step eliminating pattern is formed in advance on the second composite sheet on the internal electrode pattern forming surface of the second supporting film at a position corresponding to at least a corner portion of the dielectric green sheet. 13 will be described in detail.

(3) First, as shown in FIG. 8, a dielectric green sheet 22 is formed on the first support film 21 to prepare a plurality of first composite sheets 24. In the first composite sheet 24, the step eliminating pattern 23 is formed on at least a corner portion, for example, an outer peripheral portion, on the dielectric green sheet 22.

Further, as shown in FIG. 9, the internal electrode patterns 26 are formed on the second supporting film 25 to prepare a plurality of second composite sheets 27.

Then, the second composite sheet 27 is superposed on the first cover sheet 28 so that the internal electrode patterns 26 are located on the side of the first cover sheet 28 and pressure-bonded, and then the second support film 25. And the internal electrode pattern 26 is transferred onto the first cover sheet 28. Subsequently, the first composite sheet 24 is provided on the surface of the first cover sheet 28 on which the internal electrode pattern 26 is formed, and the step difference eliminating pattern 23 is provided on the first cover sheet 2.
After stacking and pressing so as to be positioned on the 8 side, the first supporting film 21 is peeled off to form a laminated film as shown in FIG.

Then, by using the remaining first and second composite sheets in the same procedure as described above, the internal electrode pattern, the step eliminating pattern and the dielectric green sheet are sequentially laminated to form a multilayer laminated film. After forming, the second cover sheet is overlaid. Subsequently, the obtained laminated body is heated and pressed, and cut in the thickness direction to cut out individual units. After that, the MLC is manufactured by sintering and baking a pair of external electrodes.

(4) First, as shown in FIG. 11, a dielectric green sheet 22 is formed on the first supporting film 21 to prepare a plurality of first composite sheets 24 '.

As shown in FIG. 12, the internal electrode patterns 26 are formed on the second support film 25 to prepare a plurality of second composite sheets 27 '. The second composite sheet 2
7 ', the step eliminating pattern 23 is formed at least at a corner portion of the dielectric green sheet, for example, at a portion corresponding to an outer peripheral portion.

Then, the second composite sheet 27 'is formed on the first cover sheet 28 by the internal electrode pattern 26 and the step eliminating pattern 23 by the first cover sheet 28.
After overlapping and crimping so as to be located on the side, the second support film 25 is peeled off, and the internal electrode pattern 26 and the step eliminating pattern 23 are attached to the first cover sheet 28.
Transfer to the top. Subsequently, the first composite sheet 24 ′ was superposed on the surface of the first cover sheet 28 on which the internal electrode pattern 26 was formed so that the dielectric green sheet 22 was located on the side of the first cover sheet 28 and pressure-bonded. rear,
As shown in FIG. 13, the first support film 21 is peeled off to form a laminated film.

Then, by using the remaining first and second composite sheets in the same procedure as described above, the internal electrode pattern, the step eliminating pattern and the dielectric green sheet are sequentially laminated to form a multilayer laminated film. After forming, the second cover sheet is overlaid. Subsequently, the obtained laminated body is heated and pressed, and cut in the thickness direction to cut out individual units. After that, the MLC is manufactured by sintering and baking a pair of external electrodes.

In the present invention, it is necessary that the step eliminating pattern is arranged so as to be located at least at the corners of the dielectric green sheet, preferably at four corners, more preferably at the outer periphery as described above. It is desirable to be placed in a section. Further, it is possible to dispose the step difference eliminating pattern not only in the vicinity of the outer peripheral portion but also in any region except the portion where the internal electrode pattern is formed. For example, when manufacturing an MLC using the composite sheet as described in (1) above, (a) and (b) of FIG.
As shown in FIG. 5, the step eliminating pattern 4 is formed not only on the outer peripheral portion of the dielectric green sheet 2 on which the internal electrode pattern 3 is formed but also on the inner region with a desired gap from the internal electrode pattern 3. , (A) and (b) of FIG.
As shown in, the step eliminating pattern 4 may be formed not only on the outer peripheral portion of the dielectric green sheet 2 on which the internal electrode pattern 3 is formed but also on the entire inner region except on the internal electrode pattern 3.

A method for forming the step eliminating pattern is not particularly limited, but a method such as a screen printing method, a transfer method, a gravure method, an ink jet method or the like, which facilitates formation of a thin film, is preferable.

The material of the step eliminating pattern is not particularly limited. However, it is desirable to select the same material as or similar to the dielectric green sheet or the internal electrode pattern because of the ease of shrinkage control and diffusion control in the sintering process. Particularly, in the case where the step eliminating pattern is in contact with or close to the internal electrode pattern as shown in FIG. 14 or FIG. 15, the step eliminating pattern is insulated in order to prevent an electrical short circuit. It is more preferable to use a material, for example, the same material as or a material similar to the dielectric green sheet.

The thickness of the step eliminating pattern is preferably in the range of 0.5 to 2 times the thickness of the internal electrode pattern (when dried) when dried. In particular, when the thickness of the step eliminating pattern is set in the range of 0.8 to 1.5 times the thickness of the internal electrode pattern, the pressure bonding / peeling operation becomes extremely easy.

It is desirable that the dielectric green sheet has a thickness after sintering of 20 μm or less, more preferably 10 μm or less.

The method of forming the internal electrode pattern is not particularly limited, but a method such as a screen printing method, a transfer method, a gravure method, an ink jet method or the like, which facilitates formation of a thin film, is preferable.

Although the case of using one or two kinds of composite sheets in the production of the MLC according to the present invention has been described above, in the present invention, a composite sheet in which a dielectric green sheet is formed on a support film, a support film. Prepare a plurality of 3 types of composite sheets, each of which has a pattern for internal electrodes formed on it and a composite sheet with a pattern for eliminating steps on the support film, and press and peel the composite sheets in an appropriate order. The MLC may be prepared by repeating.

[0040]

According to the present invention, when the dielectric green sheet formed on the support film is transferred, at least the corner portion of the dielectric green sheet, or the counterpart member to which the dielectric green sheet is transferred, has the dielectric Since the pattern for eliminating steps is formed at least at the portions corresponding to the corners of the green sheet, the influence of the steps in the vicinity of the corners of the dielectric green sheet due to the presence of the internal electrode pattern is used for eliminating the steps. It can be mitigated or prevented by the pattern. That is, since a step eliminating pattern having a height similar to that of the internal electrode pattern is formed at a position where the supporting film starts to be peeled from the dielectric green sheet, the dielectric green sheet is transferred onto the counterpart member. In doing so, the support film can be easily peeled off after the composite sheet is pressure-bonded.

Therefore, an MLC having a large number of laminated layers can be manufactured with a high yield. Also, the electrical characteristics and reliability of the obtained MLC can be significantly improved. In particular, the method of the present invention is effective when manufacturing a small-sized and large-capacity MLC in which the thickness of the dielectric green sheet after sintering is 20 μm or less.

[0042]

EXAMPLES Examples of the present invention will be described in detail below.

Example 1 Pb, Ba, Mg, Zn, Nb and Ti oxides were mixed in a desired composition ratio, mixed and pulverized and calcined (Pb _0.875 Ba _0.125 ) [(Mg _{1 / 3} Nb _2/3 )
A dielectric powder having a composition of _0.5 (Zn _1/3 Nb _2/3 ) _0.3 Ti _0.2 ] O ₃ was prepared. An organic binder and a solvent were added to the dielectric powder to prepare a slurry, which was coated on a synthetic resin supporting film having a thickness of 50 μm by using a roll coater and dried to have a thickness of 10 μm.
The dielectric green sheet of was formed.

Then, a conductor paste containing conductor powder of Ag / Pd = 70/30 (wt%) was applied on the dielectric green sheet by a thermal transfer device to form an internal electrode pattern having a thickness of 2 μm. Subsequently, a pattern for eliminating steps having the same material as the internal electrode pattern was formed in a grid pattern on the dielectric green sheet with a thickness of 2 μm by a thermal transfer device. After that, the obtained sheet is about 15c on a side.
It was cut into m squares to obtain 126 composite sheets having the step difference eliminating pattern formed on the outer peripheral portion.

Next, the composite sheet is placed on a first cover sheet having a thickness of about 400 μm and made of the same material as the dielectric green sheet so that the internal electrode pattern and the step eliminating pattern are on the first cover sheet side. Overlap, 30k
After pressure bonding for 10 seconds under the conditions of g / cm ² and 120 ° C., the supporting film was peeled off to form a laminated film. afterwards,
The remaining 125 composite sheets were sequentially laminated in the same procedure to form a multilayer laminated film.

Then, a thickness of about 40 is formed on the multilayer film.
At 0 μm, a second cover sheet made of the same material as the dielectric green sheet was overlaid, pressed and integrated. Then, after cutting the obtained laminate into individual units, 1050
The MLC having a size of 3.2 mm × 1.6 mm × 1.0 mm was manufactured by sintering at 2 ° C. for 2 hours and baking a conductor paste containing a conductor powder mainly containing Ag as an external electrode. In this MLC, the thickness of each dielectric layer made of ceramic was about 7 μm.

The capacity of the MLC obtained according to this Example 1,
Dielectric loss, DC withstand voltage and defect rate were measured. The results are shown in Table 1 below. The capacitance and the dielectric loss are L
It measured using the CR meter. The DC withstand voltage is MLC
It was measured from the breakdown voltage when a voltage was applied at a voltage boosting rate of 50 V / sec. The defect rate is 100 MLC
Is kept in a thermo-hygrostat at 85 ° C and 95% RH for 10V
The MLC short-circuited within 500 hours by applying the DC voltage of was determined as a defective product for measurement.

Table 1 Capacitance Dielectric loss DC withstand voltage Failure rate Example 1 6.2 μF 0.83% 390V 0% As is clear from Table 1 above, the MLC obtained in this Example 1 has excellent electrical characteristics and high It turns out that it has reliability.

Comparative Example 1 Example 1 was repeated except that a composite sheet in which a step eliminating pattern was not formed on the outer peripheral portion of the dielectric green sheet was used.
MLC was prepared by a method similar to.

In the manufacture of the MLC of Comparative Example 1 as described above, pressure bonding and peeling became difficult when the number of laminated layers exceeded 40 layers, and it was difficult to produce a uniform laminated body with 50 layers or more. .

Example 2 First, (Pb _0.7 Sr _0.3 ) (Zr _0.7 Ti _0.3 ) O ₃
Dielectric powder prepared by the hydrothermal synthesis method so as to have the composition of was prepared. An organic binder and a solvent are added to the dielectric powder to prepare a slurry, and the slurry is applied onto a synthetic resin first support film having a thickness of 50 μm using a roll coater device and dried to a thickness of 7 μm. The dielectric green sheet of was formed.

Further, a conductive paste containing conductive powder of Ag / Pd = 70/30 (wt%) was coated on a second support film made of synthetic resin having a thickness of 50 μm by a gravure apparatus and dried to a thickness of 3 μm. The internal electrode pattern was formed. Subsequently, a thickness of 3 is formed on the surface of the second support film on which the internal electrode pattern is formed by a gravure device.
A step height eliminating pattern of the same material as that of the dielectric green sheet was formed on the entire area including the internal electrode patterns with a thickness of μm.

Next, each of these sides is about 15 cm.
100 first composite sheets and 1
Each of the second composite sheets on which the step difference eliminating pattern was formed was obtained.

Then, the second cover is formed on the first cover sheet having a thickness of about 400 μm and made of the same material as the dielectric green sheet.
The composite sheet is stacked so that the internal electrode pattern and the step-eliminating pattern are located on the first cover sheet side, and pressure-bonded for 10 seconds under the conditions of 30 kg / cm ² and 120 ° C., then the second support film is peeled off Then, the internal electrode pattern and the step difference eliminating pattern were transferred onto the first cover sheet. Subsequently, the first composite sheet is laid on the surface of the first cover sheet on which the internal electrode pattern and the step eliminating pattern are formed so that the dielectric green sheet is located on the first cover sheet side.
After pressure bonding for 10 seconds under the conditions of 0 kg / cm ² and 120 ° C., the first supporting film was peeled off to form a laminated film. Then, the remaining 100 second composite sheets and 9
Nine first composite sheets were sequentially laminated in the same procedure to form a multilayer laminated film.

Then, a thickness of about 40 is formed on the multilayer film.
At 0 μm, a second cover sheet made of the same material as the dielectric green sheet was overlaid, pressed and integrated. Then, after cutting the obtained laminate into individual units,
By sintering for 2 hours and baking a conductor paste containing conductor powder mainly containing Ag as an external electrode, 3.2
MLC with dimensions of mm x 1.6 mm x 1.0 mm were manufactured. In this MLC, the thickness of each dielectric layer made of ceramic was about 5 μm.

The capacity of the MLC obtained according to this Example 2,
Dielectric loss, DC withstand voltage and defective rate were measured by the same method as in Example 1. The results are shown in Table 2 below.

Table 2 Capacitance Dielectric loss DC withstand voltage Defect rate Example 2 0.83F 0.85% 410V 0% As is clear from Table 2 above, the MLC obtained in this Example 1 has excellent electrical characteristics and high It turns out that it has reliability.

Comparative Example 2 An MLC was manufactured in the same manner as in Example 2 except that the second composite film having no pattern for eliminating the step difference was used as the second composite sheet.

In the manufacture of the MLC of Comparative Example 2 as described above, pressure bonding and peeling became difficult when the number of laminated layers exceeded 30 layers, and it was difficult to produce a uniform laminated body with 40 layers or more. .

In the above embodiment, a relaxor compound was used as the dielectric material, and Ag / Pd was used as the internal electrode material.
A conductor paste containing conductor powder of 70/30 (wt%) was used, but the present invention is not limited to this. For example, a material mainly containing barium titanate or neodymium titanate as a dielectric material, Pd as an internal electrode material,
The same results as in the embodiment can be obtained by using a paste containing Ni, Cu, etc. as a main component.

[0061]

As described in detail above, according to the present invention, even when a composite sheet in which a thin dielectric green sheet having a thickness after sintering of 20 μm or less is formed on a support film is pressure-bonded and peeled off, for example. The support film can be easily peeled off after the composite sheet is pressure-bonded, and an MLC having a large number of laminated layers can be manufactured with a high yield, and the electrical characteristics and reliability of the obtained MLC can be remarkably improved. It has a remarkable effect.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a composite sheet in which a step eliminating pattern used in a method for manufacturing an MLC of the present invention is formed.

FIG. 2 is a plan view of the composite sheet of FIG.

3 is a cross-sectional view showing a state in which the composite sheet of FIG. 1 is pressure-bonded to a first cover sheet.

FIG. 4 is a cross-sectional view showing a process of peeling the support film after the pressure bonding of FIG.

FIG. 5 is a cross-sectional view showing a first composite sheet used in another MLC manufacturing method of the present invention.

6 is a cross-sectional view showing a second composite sheet used in the MLC manufacturing method together with the first composite sheet of FIG.

FIG. 7 is a cross-sectional view showing a process in which the first composite sheet of FIG. 5 is pressure-bonded and then peeled off on the first cover sheet to which the step difference elimination pattern is transferred.

FIG. 8 is a cross-sectional view showing a first composite sheet on which a step difference eliminating pattern used in another MLC manufacturing method of the present invention is formed.

9 is a cross-sectional view showing a second composite sheet used in the MLC manufacturing method together with the first composite sheet of FIG.

10 is a cross-sectional view showing a process of peeling after pressing the first composite sheet of FIG. 8 to which the internal electrode patterns are transferred.

FIG. 11 is a cross-sectional view showing a first composite sheet used in still another MLC manufacturing method of the present invention.

FIG. 12 is a second view in which the step difference eliminating pattern used in the method for manufacturing the MLC is formed together with the first composite sheet of FIG. 11;
Sectional drawing which shows a composite sheet.

FIG. 13 is a cross-sectional view showing a process in which the first composite sheet of FIG. 11 is pressure-bonded onto the first cover sheet onto which the internal electrode pattern and the step eliminating pattern are transferred, and then peeled off.

FIG. 14 is a cross-sectional view showing another form of a composite sheet having a step-eliminating pattern used in the MLC manufacturing method of the present invention.

FIG. 15 is a cross-sectional view showing still another form of the composite sheet in which the step eliminating pattern used in the MLC manufacturing method of the present invention is formed.

FIG. 16 is a perspective view showing a structure of a general MLC.

FIG. 17 is a cross-sectional view showing a composite sheet used in a conventional MLC manufacturing method.

FIG. 18 is a cross-sectional view showing a process of manufacturing an MLC using the composite sheet of FIG.

[Explanation of symbols]

1 ... Support film, 2, 12, 22 ... Dielectric green sheet, 3, 13, 26 ... Internal electrode pattern, 4, 1
6, 23 ... Step difference eliminating pattern, 11, 21 ... First support film, 14, 24, 24 '... First composite sheet, 1
5, 25 ... 2nd support film, 17, 27, 27 '... 2nd composite film, 6, 18, 28 ... 1st cover sheet.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yohachi Yamashita 70 Yanagicho, Saiwai-ku, Kawasaki-shi, Kanagawa Toshiba Yanagimachi Co., Ltd. Yanagimachi factory

Claims (2)

[Claims] 1. A first step in which a dielectric green sheet is formed on a support film, and a plurality of internal electrode patterns made of a conductive paste are formed on the dielectric green sheet to produce a plurality of composite sheets. , The composite sheet,
The second step of stacking the internal electrode pattern on the first cover sheet so that the internal electrode pattern is located on the side of the first cover sheet and press-bonding, peeling the supporting film to form a laminated film, and the remaining composite sheet A laminated ceramic including a third step of sequentially laminating a laminated film on the laminated film in the same procedure as the second step to form a multilayer laminated film, and a fourth step of laminating a second cover sheet on the multilayer laminated film. In the method for manufacturing a capacitor, when the composite sheets are stacked and pressure-bonded, a step for eliminating the step of the internal electrode pattern between at least a corner portion of the dielectric green sheet and a facing surface of the corner portion. A method of manufacturing a monolithic ceramic capacitor, wherein a canceling pattern is interposed. 2. A first step of forming a plurality of first composite sheets by forming a dielectric green sheet on a first support film, and a plurality of internal electrode patterns made of a conductive paste on a second support film. A second step of forming a plurality of second composite sheets, and the second step on the first cover sheet.
The composite sheet is stacked from the internal electrode pattern side and pressure-bonded, and the second support film is peeled off. Then, the first composite sheet is stacked from the dielectric green sheet side and pressure-bonded, and the first support film is peeled off. By doing so, a third step of forming a laminated film in which the internal electrode pattern and the dielectric green sheet are laminated, and the remaining first step
A fourth step of forming a multi-layer laminated film by sequentially laminating a composite sheet and a second composite sheet on the laminated film in the same procedure as the third step, and stacking a second cover sheet on the multilayer laminated film. A method of manufacturing a ceramic capacitor comprising a fifth step, wherein when the first composite sheet is overlaid and pressure-bonded, at least a corner portion of the dielectric green sheet and an opposing surface of the corner portion are provided for the internal electrode. A method for manufacturing a monolithic ceramic capacitor, characterized in that a step eliminating pattern for eliminating the step of the pattern is interposed.